This invention relates generally to electrical connectors, and more particularly, to an axial connector for positioning and retaining wires and contacts in a fixed position.
Connectors exist today that are mountable to the ends of a coaxial cable. In certain applications, the cables carry one or more differential signals. For instance, quad cables are used for conveying high-speed data communications. The quad cables include one pair of transmit lines and one pair of receive lines, all of which are twisted in a helix to maintain a desired orientation with respect to one another. When a connector is attached to a quad cable, it is preferable to maintain the transmit and receive lines in a fixed geometry. The transmit and receive lines are connected to transmit and receive contacts which are located in a particular relation to one another within the connector. In the event that the spacing between, or overall geometry of, the transmit and receive lines and/or contacts is disturbed from a preferred configuration, particular receive and/or transmit lines begin to interact with one another in a detrimental manner. For example, such detrimental electromagnetic interaction may cause degradation in the signal-to-noise ratio, impedance and the like, such as cross talk and/or electromagnetic interference.
One conventional quad connector includes a tubular shell having a hollow core configured to receive a two-piece dielectric material that hold contacts connected to lines of the quad cable. The two-piece dielectric includes a rear dielectric segment stacked end-to-end with a lead guide dielectric segment, where each segment is molded separately. The lead guide segment includes a group of holes therethrough arranged in a pattern in which the contacts are held. Lead portions of each contact are loaded through the back end of the guide segment. Once loaded into the guide segment, the contacts have rear portions extending from the back end of the guide segment.
The rear dielectric segment of the two-piece dielectric is side loaded onto the rear portions of the contacts that extend from the guide segment. The rear dielectric segment is tubular in shape and includes two slots cut in the side thereof, with the slots being separated by an insulated interior wall. Rear portions of the contacts are side loaded into the slots in the split section. The slots extend along the length of the rear dielectric segment. The rear portions of the contacts are formed with a ribbed or raised peripheral segment surrounding the main body of each contact. The main body of each contact is formed with a first diameter, while the raised portion is formed with a larger second diameter. The slots cut in the split dielectric segment are notched to define a stepwise slot width having ledges dimensioned to interlock with the raised portion of each contact.
The interlocking relation formed between the slots and the raised portions of the contacts resists longitudinal movement of the contacts along the length of the rear split dielectric segment. The split dielectric segment abuts against the rear end of the guide dielectric segment, thereby preventing longitudinal movement of the split dielectric segment within the connector shell, which in turn prevents movement of the contacts along the length of the connector.
However, previously proposed connector designs have met with limited success. The connectors have very small overall size and are assembled in large quantities. The connectors have been unable to satisfactorily maintain the contacts in a desired geometry during assembly of the connector because the two pieces act independently with respect to one another. Moreover, the contacts of the connectors remain exposed to the outer shell of the connector when the dielectrics are loaded into the outer shell leading to possible failure of the connector.
A need remains for an improved coaxial connector that may be easily and reliably manufactured and assembled, and that provides insulation to the contacts of the connector.